Nuclear reprogramming, the process of converting one cell type into another by resetting the pattern of gene expression, can be achieved through forced expression of defined transcription factors. One example is the induced pluripotent stem cells (iPSCs) prepared by transducing four genes (e.g., Oct4, Sox2, Klf4 and c-Myc, called OSKM hereafter) into a cell type to be dedifferentiated. iPSCs are a type of pluripotent stem cell artificially derived by reprogramming a somatic cell. iPSCs are morphologically similar to embryonic stem cells and are capable of differentiating into a variety of different somatic cell types. This technology allows researchers to obtain pluripotent stem cells for use in a research setting. iPSCs also have therapeutic uses for the treatment of disease without the need for stem cells derived from an embryonic source.
However, generally less than 1% of transduced cells are reprogrammed to form iPSCs, and the entire process of establishing iPSC clones is long (over a month).